Measurement of the Stefan-Boltzmann constant

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Homework Help Overview

The discussion revolves around the measurement of the Stefan-Boltzmann constant, focusing on the correct representation of the value and its associated uncertainty. Participants are examining the formatting and precision of their reported results.

Discussion Character

  • Conceptual clarification, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • Participants are questioning the accuracy of their reported value and the appropriate way to express uncertainty. There are discussions about the number of decimal places in the measurement and the correct notation for units.

Discussion Status

Some participants have provided guidance on formatting and precision in reporting measurements. There is an ongoing exploration of how to properly express the Stefan-Boltzmann constant, with various interpretations being discussed.

Contextual Notes

Participants mention that the measurements were not taken with high-precision instruments, indicating a focus on learning rather than achieving precise values. There are also concerns about the representation of units and the need for consistency in decimal places.

MatinSAR
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Homework Statement
Report the measurement result of the experiment.
Relevant Equations
None.
I've written it as :
1720087985562.png

The mentor indicated that this is incorrect. How can I write it correctly?
My try: $$ \sigma = 1.07 \times 10^{-8}W.m^{-2}.k^{-4} \pm 0.0243 \times 10^{-8} W.m^{-2}.k^{-4} $$
 
Last edited:
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MatinSAR said:
Homework Statement: Report the measurement result of the experiment.
Relevant Equations: None.

I've written it as :
View attachment 347777
The mentor indicated that this is incorrect. How can I write it correctly?
My try: $$ \sigma = 1.07 \times 10^{-8}W.m^{-2}.k^{-4} \pm 0.0243 \times 10^{-8} W.m^{-2}.k^{-4} $$
First, I assume you mean the Stefan-Boltzmann constant.
The value is somewhat off. https://www.techtarget.com/whatis/definition/Stefan-Boltzmann-constant gives five times as much.
You have more decimal places in the error range than in the central value. But I am not sure whether you should round it to 0.02 or 0.03.
Also, in the typed form above, you have k instead of K.
 
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haruspex said:
First, I assume you mean the Stefan-Boltzmann constant.
Yes, I edited that.
haruspex said:
The value is somewhat off.
We did not use high-precision instruments. The main goal was to learn more about blackbody radiation, rather than focusing on obtaining precise measurements of the constant.
haruspex said:
You have more decimal places in the error range than in the central value. But I am not sure whether you should round it to 0.02 or 0.03.
Also, in the typed form above, you have k instead of K.
Thank you for your help. $$\sigma = 1.07 \times 10^{-8}W.m^{-2}.K^{-4} \pm 0.02 \times 10^{-8} W.m^{-2}.K^{-4} $$
 
In addition to what @haruspex said...

If using the form ##a \pm b##, use the same number of decimal places for ##a## and ##b## The units are written only once.

For example, a distance in metres:
##11.0032 \pm 0.0008## m.

For example, a time in seconds using standard form:
##(9.20 \pm 0.15) \times 10^{-6}## s
(some people don’t use the brackets).

There is another common method. The above examples can be written more succinctly as
##11.0032(8)## m and
##9.20(15) \times 10^{-6}## s.

Edit -typo
 
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Steve4Physics said:
In addition to what @haruspex said...

If using the form ##a \pm b##, use the same number of decimal places for ##a## and ##b## The units are written only once.

For example, a distance in metres:
##11.0032 \pm 0.0008## m.

For example, a time in seconds using standard form:
##(9.20 \pm 0.15) \times 10^{-6}## s
(some people don’t use the brackets).

There is another common method. The above examples can be written more succinctly as
##11.0032(8)## m and
##9.20(15) \times 10^{-6}## s.

Edit -typo
I get it. Thank you for your time.
 
The units should also be typeset in non-italics, and there should be a space between the number and the units.
 
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vela said:
The units should also be typeset in non-italics, and there should be a space between the number and the units.
I will keep this in mind for the future. Thank you.
 

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